Abstract
Molecular diagnostics is defined as a field of laboratory medicine in which the principles and techniques of molecular biology are applied to the study of disease. This book is edited by the same editors as the Tietz Textbook of Clinical Chemistry and Molecular Diagnostics and originated from the realization that the rapidly expanding area of molecular diagnostics warranted publication of a book dedicated to the subject.
The book is divided into three main sections. The first covers the basic principles of molecular biology and describes the alterations which can occur in nucleic acids and the genome. The second section covers the techniques and instrumentation used in molecular diagnostics. Specimen requirement and collection are discussed, and this is followed by a short chapter covering methods used for the isolation of nucleic acids including the use of automated platforms. A chapter is devoted to the techniques used for amplification, detection and discrimination of nucleic acids and includes detailed but readable descriptions of the various applications of the polymerase chain reaction, the use of reporter molecules and labelled probes, electrophoretic techniques and the use of hybridization assays. The applications and limitations of miniaturization through the use of DNA chips and devices are comprehensively and well discussed. The design and operation of a molecular diagnostics laboratory is also covered and the section concludes with a particularly useful introduction to evidence-based molecular diagnostics.
I particularly enjoyed the third section, which is devoted to the applications of molecular diagnostics and is highly informative and well written. The section opens with a summary of inherited diseases and describes the differences between autosomal recessive, autosomal dominant and X-linked diseases with Mendelian inheritance compared with diseases with non-Mendelian inheritance. Specific diseases that exemplify the different patterns of inheritance are explained in detail and beautifully illustrate the use of molecular diagnostics in the diagnosis of inherited diseases.
The second chapter explains how genetic variation can be analysed and used in identity assessment, parentage testing and engraftment studies. The application of molecular microbiological testing in the diagnosis and monitoring of infectious diseases is then fully reviewed with reference to a range of specific pathogens. An interesting chapter on pharmacogenetics addresses the molecular diagnostic tests that are used to detect allelic variants of drug metabolizing enzymes. It particularly focuses on the relationship between genotype and phenotype, unique testing methods and the clinical applications of testing for seven key genes, including thiopurine S-methyltransferase and several cytochrome P450 variants. The final chapter covers the use of molecular genetics in the diagnosis of human cancers explaining their application in lymphomas, leukaemias and solid tumours.
The appendix has some extremely useful reference information including informative sections on the features of selected oncogenes and selected tumour-suppressor genes.
Each chapter follows a similar format particularly designed with the student in mind. A brief outline summary of the content is followed by a list of learning objectives that the reader should aim to achieve after reading and understanding the text. A list of ‘Key Words and Definitions’ at the start of each chapter is extremely helpful. These keywords are highlighted in bold throughout the following text, facilitating rapid clarification of their definitions, something that is particularly useful for those of us less comfortable with the terminology involved. At the end of each chapter is a list of references followed by a series of review questions that enable the student to test their comprehension of the chapter content.
Additional useful features aimed towards the student are the separation of ‘Advanced Concepts’ from the main body of text. These are concepts that broaden the area of discussion to a level beyond that required by the majority of students but may be useful for those with a more specialist interest. Ethical issues are particularly pertinent to the field of molecular diagnostics and there are separate ‘Ethics Boxes’ in many of the chapters that raise important ethical issues for the reader to contemplate.
Overall, I think this will be an extremely useful reference book for clinical scientists of all grades and a valuable addition to any clinical laboratory. I wonder whether it is perhaps almost too detailed to warrant purchase by Grade A trainees but for those studying for MRCPath and with a more specialist interest it would certainly be an excellent source of information.